running rich, stalling, black smoke

[JDAWG]

Ok just got my Shelby Daytona VNT on the road yesterday. Yesterday it ran great. Today on the way to work it stalled at a stoplight and was hard to start. Well got it started and kept wanting to stall. Had to drive around a bit and the same thing. Under a hard load like going up a hill. and moderate boost it bellows black smoke. And it ate alot of gas from what I think. So its running rich. Weird thing is it wouldnt blink codes. Light just stays on and when I start it then it goes off. I did find 2 wires that were chafed by a belt, I think they went to the injector harness, and I taped them up. So anyways I grabbed the DRB from work and ran dtc, I came up with this (sorry they dont give you the actual number like when it blinks) Auto shutdown x starts since set, o2 shorted to voltage, and injector 2 & 3 circuit control. Any ideas anyone? I am taking the DRB home so if anyone has any info like the map should be this voltage or injector pulsewidth should be this that would be great because I can read all that. The car just hunts at idle then stalls, and of course black smoke past mid boost going up a big hill. Thanks

[GLHSKEN]

Check the injector grounds and for broken wires on the inj harness.

[shadow88]

+1 That's exactly what happened to mine when I found the ground on the fuel rail was loose due to a stripped manifold hole. Same codes and all.

[JDAWG]

SO there are 2 bolts that hold the fuel rail right? One is supposed to have a ring on it for an injector harness right? Well i sure as hell dont see one. All the injectors use the same ground right? Each one has a green and black wire that comes off of it and all these go together then go into the big harness that goes around to the sbec. Does this ground somewhere? Or does it ground to the pcm? Ill go back out and look and try to follow the harness to see if it has a ground somewhere.

On a side note the streets are a little damp here, oh man what fun, by 3k rpms both tire are smoking just puttin it to thr floor in 1st lol.

[shadow88]

On my car (88 t2) the injector ground is on the passenger side fuel rail mounting bolt. Yes there are 2 bolts (assuming you have an 88+ turbo 1 or 2)

[JDAWG]

well i looked at it there is not ring. Its a turbo IV. I looked at my 88 sundance t1 and yea it has it. On the Daytona it has a big plug and ALL the wires for the injectors plug into it. I suppose it grouns somewhere along the way. Only problem is I dont see any. Maybe a sbec car ground it through the pcm. Not sure if it doesnt, ill just shop the wire and ground it on my own.

[JDAWG]

well that one green and black wire that all the injectors connect to isnt a ground. I cut some sheilding off it a multimetered it. And for some reason if I unplug the o2 sensor it runs better and doesnt stumble as much at idle. I really dont think the 2 are related but I am going to put a new one in tomorrow and see what happens.

[LynX853]

loose o2 connector will do that too

[Pat]

+1 on the grounds. There is probably a ground wire from the injector harness that grounds to one of the rail to manifold bolts. There also should be a ground strap from the rail to manifold bolt to the firewall.

Where did you pick up a VNT from? Was this Joe's while/maroon car that he was selling?

[JDAWG]

yea it was pat, ill look over it again tomorrow after work, didnt have alot of time today, got off at 7, they ran me out lol. Plus its dark out now and all I have is a flashlight. I swear I dont see one on the rail. But the one from the manifold to the firewall is there and ok. I just kinda got tired of working on it tonight. Really its a sweet car. It runs super good except for this Plenty of power. I just hate doing the heel/toe thing around town lol.

[JDAWG]

Ok couldnt get the O2 out. So hosed it down with penetrating oil, and will do it all day tomorrow. But guys I swear there isnt a ground on the fuel rail, i looked everywhere around there. I know the exact ground cause my 88 has it and I forgot to hook it up once and the car wouldnt start. Anyone have a 90 or newer that does have the ground? Multimetered the other one on the back of the intake and its good. I erased the codes last night and they didnt come back. I idles alot better with the O2 unhooked. But plug it in and it runs like ----. Hopefully I get this O2 in tomorrow and everything is ok, but guess I have to go from there.

[puppet]

Just curious ... what temp rating is the t-stat? Plugs sooty?
If it's a 180* drop a 195* one in and see if this clears up.
Also, have you checked the FP at the rail?

[paratender2003]

also there is an intake ground. what about a vac line that came loose?

[JDAWG]

Just curious ... what temp rating is the t-stat? Plugs sooty?
If it's a 180* drop a 195* one in and see if this clears up.
Also, have you checked the FP at the rail?

honestly not sure what stat he has in there, it takes a loooooooonnnnnggggggggg time to warm up, i am assuming a 180 stat, but i dont think that can cause these problems. Tomorrow I am going to check the fuel pressure and pull plugs, plus stick the O2 in and see whats going on after that.

[CUDA 1]

The injectors share a common power (dark green w black tracer) the ground to each injector goes to the sbec which cycles each injector by providing the ground signal. Your problem might be on the power side because this power comes from the asd relay and also feeds power to heater on the o2 sensor. With the codes you have setting you could possibly have a shorted injector or short in the injector harness. Since a code is setting for #2 and #3 try checking the resistance of both these injectors. Another thing you could do is erase the codes and see which ones come back to eliminate any you might have set yourself or fixed with that harness repair you made.

[JDAWG]

hmm weird, i erased codes last night, drove home, drove to this work this morning, only 1 code, O2 stays at center. I did fix a couple vac lines last night that didnt look good. Guess Ill get the O2 in after work and see what happens

[JDAWG]

oh just to let everyone know, the injector harness is not in the catalog for a 90 VNT G body, its only in the catalog for a J and P for some reason. Mine had a tag on it pn 4481505 and they are still available

[GLHSKEN]

Anyone have a 90 or newer that does have the ground? .

Yep, My 90 daytona has the same fuel set-up you do, no separate ground.. Make sure the ground strap is on the pass side mount to frame rail and the strap from the intake to firewall is in place

[zin]

So anyways I grabbed the DRB from work and ran dtc, I came up with this (sorry they dont give you the actual number like when it blinks) Auto shutdown x starts since set, o2 shorted to voltage, and injector 2 & 3 circuit control. Any ideas anyone? I am taking the DRB home so if anyone has any info like the map should be this voltage or injector pulsewidth should be this that would be great because I can read all that. The car just hunts at idle then stalls, and of course black smoke past mid boost going up a big hill. Thanks

The auto shut down and black smoke make me think it could be MAP related, or at least a part of the problem. The voltage with key on/engine off should be about 2Volts, if it's higher (as in a bad sensor), it'll make the computer think you are under a heavier load or in boost and dump a bunch of fuel and/or go into overboost shutdown. While you have the DRB it's too easy to not check. Man, I'm glad I finally got a OTC 4000, saved me sooo much headache!

Mike

[JDAWG]

Ill look at that tonight, thanks. I couldnt get the O2 out, so someone is going to help me today or tomorrow after work